Extract NativeAppWindow from src/extensions

apps/ui/views/app_window_frame_view.h

Index: apps/ui/views/app_window_frame_view.h
diff --git a/apps/ui/views/app_window_frame_view.h b/apps/ui/views/app_window_frame_view.h
index 7ab2d4c0969d611926495c830ea375e337ffdfa0..433167feafee7683506e0d6ba86d9548cb7969b4 100644
--- a/apps/ui/views/app_window_frame_view.h
+++ b/apps/ui/views/app_window_frame_view.h
@@ -16,15 +16,15 @@
 
 class SkRegion;
 
-namespace extensions {
-class NativeAppWindow;
-}
-
 namespace gfx {
 class Canvas;
 class Point;
 }
 
+namespace native_app_window {
+class NativeAppWindow;
+}
+
 namespace ui {
 class Event;
 }
@@ -51,7 +51,7 @@ class AppWindowFrameView : public views::NonClientFrameView,
   // TODO(benwells): Refactor this to split out frameless and colored frame
   // views. See http://crbug.com/359432.
   AppWindowFrameView(views::Widget* widget,
-                     extensions::NativeAppWindow* window,
+                     native_app_window::NativeAppWindow* window,
                      bool draw_frame,
                      const SkColor& active_frame_color,
                      const SkColor& inactive_frame_color);
@@ -99,7 +99,7 @@ class AppWindowFrameView : public views::NonClientFrameView,
   SkColor CurrentFrameColor();
 
   views::Widget* widget_;
-  extensions::NativeAppWindow* window_;
+  native_app_window::NativeAppWindow* window_;
   bool draw_frame_;
   SkColor active_frame_color_;
   SkColor inactive_frame_color_;